Designfusion Blog

NX CAM: Options for selecting cut areas

John Pearson - Thursday, May 26, 2016

With the daily grind to meet production schedules, it is often difficult to keep up with all the changes to NX CAM software. I have spoken with many users
who are basically still using methods that they learned from their first CAM course(s), despite the fact that there now exist more efficient ways of
doing things. The primary reason for this is that they have not received any update training. Some companies expect the users to learn on their own,
yet fail to provide time to do so. Others don’t see the value in upgrade training, or insist that their users simply don’t need it. Whatever the excuse,
training always seems to be the lowest priority, until issues arise. I have even known companies who have even investigated changing software, when
the far less expensive option of training would provide them with all that they need.

With this in mind, I thought it may be ideal to review some of the newer and more efficient ways of doing things in NX CAM. For this blog article I’d like
to focus on the new options for cut area selection, added to the fixed and variable contour operations, in NX9. You can now define Cut Areas, for these
operations, by selecting a seed face and bounding edges that form a closed loop.

Example 1: Let’s start by looking at a simple example where I use a seed face inside a single loop. Here I have a Contour Area operation for the part you see below.

I start by selecting the Specify Cut Area option. I then use the new selection method that has been added. This
method is labeled as Edge Bounded Region, and is found in the Selection Methodlist.

With this new option selected, all I have to do is select a seed face, as shown below.

Then I select the bounding edge as shown below.

Tip: To ensure the selection of the tangent curve, I make sure that the selection intent, on the Top Border Bar,
is set to Tangent Curves.

I then click on Preview Region, and notice that I have selected this entire region with minimal mouse clicks.

Example 2:This example shows the selection of a single seed face that is found between two containment loops.
Using the same part and operation as in Example 1, I start by selecting Specify Cut Area. I select the Edge Bounded Regionoption from theSelection Methodlist. This time I select the seed face shown below.

As before, I use the Tangent Curves selection intent to select the top closed loop.

I then select the bottom closed loop.

These two closed loops form the exterior and interior containment loops and when I select Preview Region, I am shown the selected area.

If you expand theRegion Options on theCut Areadialog, you will see
2 other options, the Traverse Interior Edgesoption, and the Use Tangent Edge Angleoption.

The next two examples will look at these options.

Example 3: Using theTraverse Interior Edgesoption.

In this example, I expand on Example 1, where I have already selected the faces as shown below.

But in this example, a boss and an additional edge blend has been added to the model.

If I use the same selection method as in Example 1, but also toggle on Traverse Interior Edges, the Preview Region shows me the following selection area.

Example 4: Using the Use Tangent Edge Angle option.

In this final example, I have modified the part by removing the top edge blend. By removing the edge blend, the normal vectors between the faces now form
a 30-degree angle.

I start by selectingSpecify Cut Area. I select theEdge Bounded Regionoption from the Selection Methodlist. For my seed face I select the bottom face.

For the bounding edge I select the four exterior edges shown below.

Next, I toggle on theUse Tangent Edge Angle option and set the Angle Tolerance to 25.0000, as shown.

When I generate my operation, I notice that the top planar face is ignored. This is because the normal vectors between tangent faces exceed the specified
25-degree Angle Tolerance, therefore the adjacent face is not included in the cut area.

Rule:If the normal vectors between tangent faces equal or exceed the user specified Angle Tolerance, the
adjacent face is not added to the contained area to be machined.

As you can see, these new options are more efficient than the previous method for selecting a cut area. And this is just one of the many new tools added
in recent years. NX CAM continues to improve its technology, but it is up to you, the user, to learn about these improvements. It has been my experience
that this does not happen unless the user is allowed the time to learn. The most cost effective way for users to improve is through professional training.
Update and custom courses are available through either Siemens Training or through Designfusion. For more information, contact your Account Manager
or contact us at [email protected].